Dry razor having a spring means to open the razor head



Sept. '13, 1966 J. H. POLETIEK 3,271,857

DRY RAZOR HAVING A SPRING MEANS TO OPEN THE RAZOR HEAD Filed March 5, 1964 INVENTOR.

JOHANNES H. POLETIEK AGENT United States Patent ,81 4 Claims. (Cl. 3041.6)

This invention relates to dry-shaving apparatus in which a covering plate is fitted on a housing so as to be capable of being swung open. Specifically a shaving head is adapted to accommodate at least a cutter plate of a dry-shaving apparatus and has its peripheral lower edge adjoining the edge of the opening of the housing, a spring being provided which causes the covering plate to be swung open after a closure is unlatched.

An object of the invention is to simplify the swinging and fixing device thus required for the head while retaining a reliable operative device and at the same time reducing as far as possible the manufacturing and assembling cost thereof.

Such a construction is convenient for a shaving head to permit the head to be cleaned after use, such as by blowing out the hair chamber, without a need of removing the whole of the shaving head. It is then only necessary, for example, to depress an unlatching button by a finger of the hand holding the apparatus and the head swings open, whereafter it can be closed again without the other hand having to be used in this operation.

It is also preferable that the periphery of the head adjoins the upper edge of the housing with uniform transition and without slits being formed through which hairs could penetrate from the hair chamber to the exterior.

A device according to the invention attains these objects in that one end of a spring element is fixed to the lower side of the covering plate and its other end engages under spring pressure, but otherwise freely, an inclined guide surface on a side wall of the housing, the moment of the spring being so directed that the force exerted on the spring element by the guide surface causes the covering plate to be swung open while the free end of the spring element slides up along the guide surface.

In this embodiment a single spring of simple shape is sufficient which can cause the shaving head, after release to be swung open as well as to maintain the shaving head in its open position.

As will appear hereinafter, the construction can thus readily be made such that a separate spindle for the swinging movement of the covering plate is not required and, if desired, the cover may also be completely removed without complications, for example to replace it by an auxiliary fixture, such as a hairclipping device, when used on a dry-shaving apparatus.

An advantageous embodiment is characterized in that the free end of the spring engages an inclined inwardlyextending guide surface on the swing side of the housing and the spring makes an acute angle with the said surface as well as with the lower surface of the covering plate, the spring force being directed towards the lastmentioned lower surface.

Since the spring always tends to engage the lower surface of the shaving head and thus make the angle between said lower surface and the spring as small as possible, the free end of the spring climbs of its own accord along the said guide surface after the shaving head is unlatched, thereby pushing the shaving head into its open final position in which the angle made between the spring and the lower surface of the shaving head is considerably reduced.

One preferred embodiment is an arrangement in which the guide surface has a projection behind which the free end of the spring engages when the covering plate is completely swung open.

The single spring thus also provides for blocking of the shaving head at its open position.

In order that the invention may be readily carried into effect, it will now be described in detail, by way of example, with reference to one embodiment shown in the accompanying diagrammatic drawing, in which description several further details will be set forth which may advantageously be used.

FIGURE 1 is a cross-sectional view along the main axis through the portion of a housing comprising a shaving head, to which the invention is applied and FIGURE 2 is a plan view of the spring used therein.

In FIGURE 1 the shaving head is indicated by the reference numeral 1 and the housing of the apparatus by the reference numeral 2. The shaving head closes a chamber 3 in the housing through which one or more driving spindles extend along the center line 4, shown in dot-anddash line. They drive, for example in a rotary manner, one or more cutting members, the cutting system being housed in a cavity 5 of the shaving head 1, while the capshaped cutting plates may project more or less above the surface of the shaving head through apertures provided therein. All this is not shown in the figure since such devices are fully known and need no further explanation for proper understanding of the invention.

FIGURE 1 also shows that a peripheral lower edge 6 of the shaving head rests on an edge 7 of the opening of the portion of the housing supporting the shaving head. A U-shaped spring 8 having the ends 9 of its legs fixed in the housing 2, engages through its U-shaped portion 10 with an inclined upwardly-extending surface 11 of a latch 12 which forms part of the shaving head 1, so that the latter is held fast and attracted in its closed position until an unlatching button 13 is depressed and pushes the spring 8 inwards. The shaving head 1 will then swing open under spring pressure and this is achieved as follows.

Outwardly-bent ends 15 of legs 16 of a U-shaped resilient element 14 are secured to the lower side of the shaving head 1, the bight portion 17 of the said resilient element engaging an inclined inwardly-extending guide surface 18 on the swing side of the housing 2. Although the spring action of the U-spring 14 could also be obtained by fixing and twisting the ends 15, in this example a torsion spring 19 is used at one or either end (see FIGURE 2), one end of said spring being rigidly connected to the shaving head 1 and its other free end being formed as a pin 20 which tends to turn over the U-shaped element against the lower surface of the shaving head. The force exerted on the bight portion 17 of legs 16 at its point of application 22 on the wall of the housing 2 thus constitutes a force which tends to swing the shaving head open.

It can be seen that the legs 16 of the spring make an acute angle with the guide surface 18 as well as with the lower surface of the shaving head 1 and since the spring force is directed to the last-mentioned surface as indicated by arrow P, it tends to make the angle Y between the spring element 14 and the lower surface of the shaving head 1 as small as possible. Consequently, after unlatching, the bight portion 17 climbs up along the guide surface 18 and the shaving head is pushed up into the position shown in broken line in FIGURE 1. In the final position the bight portion 17, which constitutes the free end of the spring, engages behind a projection 23 of the guide surface 18, thus blocking the swinging movement and determining the final position of the shaving head swung open.

It can furthermore be seen that the spring 14 exerts at any position a force on the shaving head which pulls the lower edge on the swing side inwards, this edge at the same time being drawn, at 21, onto the supporting edge of the housing. By providing a collar 24 on the edge of the opening of the housing, the portion 21 of the edge, which is rounded and about which the shaving head turns,

'will thus steadily be drawn into the corner between the collar 24 and the upper surface of the edge of the housing, thus making a separate hinge spindle superfluous.

This affords the important advantage that the shaving head can now also be completely removed in a very simple manner, namely by removing the bight portion 17 from under the projection 23. It will also be evident that a single movement of the hand is sufficient to reclose the shaving head after being swung open and also to replace it after having been removed, while a single spring element 14 only is required for the whole of the device.

The U-spring 1-4 will not at the least be a disturbing element in the chamber 3 since the legs 16 are located varound the driving device and can extend along the wall of the chamber 3. It is also not imperative to use torsional spring force since the ends 15 of the U-spring can be rigidly secured and at the position shown in FIGURE 1, the spring can be sufiiciently prestressed by bending it downwards from an initial position. In this case the spring will initially have an upwardly curved shape or, in contrast with FIGURE 1, it will have a curved shape in its operating position.

What is claimed is:

1. A shaving head for a dry shaver having a housing and including a shear plate adapted to swing open from a normally closed horizontal position to an open, generally vertical position, said housing being provided with an inclined wall, means mounting said shaving head on the housing of said dry shaver with the peripheral lower edge thereof abutting and engaging a portion of the edge of the opening of said housing, said means comprising a spring having one end secured to the underside of said shaving head and another portion thereof freely and slidably engaging the inclined wall of said housing, the moment of force on said spring being so directed by said inclined wall that the shaving head is swung open when said portion of the spring slides up said inclined wall.

2. A shaving head for a dry shaver as claimed in claim 1 wherein said inclined wall extends inwardly in said housing and said spring makes an acute angle with the undersurface of said shaving head and said inclined wall.

3. A shaving head for a dry shaver as claimed in claim 1 wherein said inclined wall is provided with a projection behind which said portion of said spring engages at the open final position of said shaving head.

4. A shaving head for a dry shaver as claimed in claim 1 wherein said spring element is U-shaped, the two ends of the legs of said spring being secured to said shaving head, and the bight portion thereof engaging and slidable along said inclined wall.

References Cited by the Examiner UNITED STATES PATENTS 2,637,901 5/1953 Kahn et al 30-416 2,780,864 2/1957 Kleinman 3041.6

FOREIGN PATENTS 1,091,901 10/1960 Germany.

WILLIAM FELDMAN, Primary Examiner. MYRON C. KRUSE, Examiner. 

1. A SHAVING HEAD FOR A DRY SHAVER HAVING A HOUSING AND INCLUDING A SHEAR PLATE ADAPTED TO SWING OPEN FROM A NORMALLY CLOSED HORIZONTAL POSITION TO AN OPEN, GENERALLY VERTICAL POSITION, SAID HOUSING BEING PROVIDED WITH AN INCLINED WALL, MEANS MOUNTING SAID SHAVING HEAD ON THE HOUSING OF SAID DRY SHAVER WITH THE PERIPHERAL LOWER EDGE THEREOF ABUTTING AND ENGAGING A PORTION OF THE EDGE OF THE OPENING OF SAID HOUSING, SAID MEANS COMPRISING A SPRING HAVING ONE END SECURED TO THE UNDERSIDE OF SAID SHAVING HEAD AND ANOTHER PORTION THEREOF FREELY AND SLIDABLY ENGAGING THE INCLINED WALL OF SAID HOUSING, THE MOMENT OF FORCE ON SAID SPRING BEING SO DIRECTED BY SAID INCLINED WALL THAT THE SHAVING HEAD IS SWUNG OPEN WHEN SAID PORTION OF THE SPRING SLIDES UP SAID INCLINED WALL. 